Some of the world's top space boffins have proposed a new way to figure out the odds of finding life - but not as we know it - on another planet.
The brainy bunch, composed of scientists from NASA, SETI, the German Aerospace Centre and four universities, suggested that so far our search for life in the universe has …

COMMENTS

finally

It's about time boffins took this idea seriously. Assuming extraterrestrial life exists, and developed independently (as opposed to the far-fetched 'mysteriously seeded from outer space' theory), there's no reason it needs to be remotely similar to life as we know it. Many years ago, Isaac Asimov hypothesized on the various liquid media life could potentially exist in. Depending on temperature range, these include water, ammonia, hydrocarbons, and silanes (like hydrocarbons, but replacing carbon with silicon). Ammonia-based life might function somewhat like ours, but the others would have a truly alien biology, unlike anything we've ever seen.

Star Trek not true then?

Expect the unexpected

If we ever find alien life somewhere in the universe there is only one thing that is certain, it will not be what we expect it to be. There is no reason to believe that their biochemistry will be any exception to this.

Points to Isaac Asimov for suggesting some non-hydro-carbon-oxygen life-platform candidates, but he probably missed the majority of candidates.

We are barely able to understand how our own biochemistry works, we simply haven't got the means to rule out anything but the most rudimentary static environments as options for life.

The only thing that hydro-carbon-oxygen has got going is that our statistical material (an impressive 1 sample) suggest that it is relatively more likely that hydro-carbon-oxygen environments has a high chance of developing life than other environments.

I think this a case where a little knowledge might be more dangerous than no knowledge, for all we know, it could be that hydro-carbon-oxygen actually has a much lower chance of spawning life than some other environments, and we just got lucky.

I agree to expect the unexpected but I guess there are some very important assumptions about life that we do know about:

- made of largely of high valency elements, carbon & silicon to allow construction of complex molecules (= variety of function)

- requires a source of nutrients, to make more carbon / silicon copies of itself

- needs a transport medium (e.g. water, liquid methane, etc.)

However not to say anything about the size of any 'entity', who's to say the largest organisms 'of the order of a metre' are about as big as they get? This is where we get to the Gaia concept, and possibly larger, if we involve stellar objects.

A bigger problem is our definition of life. We may not actually recognise life for what it is when we find it.

Master of Paxwax, a two-part novel by Philip Mann is a good read about mature human / alien interaction